1. Field of the Invention
This invention relates to an apparatus for treatment of specimens, and more particularly, to an apparatus for treatment of specimens with numerous treatment containers representing treatment stations. The treatment containers are set up to receive treatment solutions for the specimens. Such apparatuses are particularly used for staining histological or cytological specimens or for embedding histological or cytological specimens in an embedding medium.
2. Discussion of Relevant Prior Art
Automatic staining machines with treatment baths arranged in a 2-dimensional grid array are known, for example, from Japanese Patent JP-63-208761, European Patent EP-B1 0 586 494, WO 93/23732 and U.S. Pat. No. 4,738,824. These apparatuses have a transport device by means of which the specimens to be treated are transported from one treatment station to the next treatment station according to the program, are deposited for the prescribed treatment time in the next treatment station, and are subsequently removed. The control of the course of the program takes place completely automatically, by means of built-in processors or by means of a PC with attached keyboard and display. The treatment programs can be input and stored. The desired treatment program is subsequently selected according to requirements, called up, and automatically executed. Parallel runs of different stored treatment programs are also possible, for the most part.
To prevent health hazards due to vapor products of the solvents used (principally ethanol and xylene), a part of the known apparatuses has a hood-like equipment cover from which the solvent vapors arising in the equipment are sucked out through filters. For the most part, additional bath covers for baths or groups of baths are offered, to be placed manually on the baths or groups of baths outside the operating times, in order to prevent undesired amounts of evaporation.
A general problem with such treatment apparatuses is the prevention of the transfer of liquids from bath to bath during the course of the individual dipping processes. This is important because contamination of the baths with liquids from other baths leads to a qualitative worsening of the staining results and thus also affects the reproducibility of the results of staining. To prevent such carry-over of liquid, it is known from European Patent EP-B1 0 586 494 to provide a dripping zone between the treatment containers. The transport of the specimen or specimens between successive baths takes place along this dripping zone. However, such a dripping zone tends to encumber a compact arrangement of the baths and thus to obstruct the compactness of the whole treatment apparatus, since a free space to serve as a dripping zone is required between the individual baths.